2016/12/31 by J. Fernandez Afonso, J. Fernández Afonso, J. Kuneš +1
Engineering · Materials Science · Mathematics · Physics and Astronomy · #Algorithm #Crystal Structures and Properties #Magnetic and transport properties of perovskites and related materials #Mathematics #Perovskite Materials and Applications #Physics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.95.115131
published as Phys. Rev. B 95, 115131 (2017) · published version
openalex created_date 2017/01/06 · openalex publication_date 2017/03/15 · arxiv created 2017/03/16 · arxiv updated 2017/03/17 · openalex updated_date 2026/08/05
We use the LDA+U method to study the possibility of exciton condensation in perovskites of transition metals with the d6 electronic configuration such as LaCoO3. For realistic interaction parameters we find several distinct solutions exhibiting a spin-triplet exciton condensate, which gives rise to a local spin density distribution while the ordered moments are vanishingly small. Rhombohedral distortion from the ideal cubic structure suppresses the ordered state, contrary to the spin-orbit coupling which enhances the excitonic condensation energy. We explain the trends observed in the numerical simulations with the help of a simplified strong-coupling model. Our results indicate that LaCoO3 is close to the excitonic instability and suggest ways how to achieve the exciton condensation.